A technique for detecting raindrop attached to a windshield in order to automate wiper control while a car runs and a technique using an illumination and an optical filter that passes only a wavelength of illumination light to cause a sensing camera for detecting a lane and the like to also detect raindrops attached to a windshield are known in the past.
For example, Japanese Patent Application Laid-open No. 2005-195566 discloses an image processing system having an image processing apparatus, a light source, and an optical filter for the purpose of using them as not only a sensing camera but also a camera for detecting raindrops, and tracking outside light that changes from time to time by emitting light from the light source and capturing images of raindrops at the outside of the windshield, thus changing the intensity of prepared illumination.
However, in a technique using the configuration as not only a sensing camera but also a camera for detecting raindrops such as the conventional techniques described above, it is necessary to track outside light that changes from time to time and adjust the exposure of an optical filter portion, and accordingly, it is necessary to change the intensity of the prepared illumination. For this reason, an extremely powerful illumination is required, which causes a problem in that the power consumption increases.
In the conventional technique, powerful outside light needs to be emitted to the outside of the vehicle, and this requires higher degree of safety to be ensured.
Therefore, there is a need for an image processing apparatus, an image-capturing method, and a vehicle capable of reducing the power consumption and capable of improving safety even when an image-capturing unit is used not only for sensing but also for detection of objects.